Raman depolarization ratios and order parameters of a nematic liquid crystal

作者: K. Miyano

DOI: 10.1063/1.436508

关键词: Molecular physicsChemistryRaman spectroscopyCrystallographyLiquid crystalTensorMoleculeExcited stateSpectral lineRaman scatteringDepolarization

摘要: The depolarization ratios of the Raman vibrational bands from terminal C≡N and central C–C biphenyl link an oriented nematic liquid crystal [p‐n‐pentyl‐p′‐cyanobiphenyl (5CB)] have been measured. orientational order parameters 〈P2〉 〈P4〉 were calculated. parameter remained far less than mean‐field theory prediction although a systematic discrepancy between obtained two was noted. tensor band found not to be uniaxial, contrary previous assumption, strong association molecules is suggested. Problems associated with this technique are discussed.

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